Table 1 Detailed demographic variables and covariates divided by smoking categories

From: Cigarette smoking and thinning of the brain’s cortex

 

Never smoked n=245

Ex-smokers n=223

Current smokers n=36

Age at MRI (years)

72.7±0.7 (71.2–74.2)

72.7±0.8 (71.0–74.2)

72.7±0.6 (71.6–73.9)

Gender

Female=136 (55.5)

Female=104 (46.6)

Female=20 (55.6)

 

Male=109 (44.4)

Male=119 (53.4)

Male=16 (44.4)

IQ at age 11 years

101.6±15.2 (38.5–128.0)

101.8±14.3 (62.1–129.9)

99.8±10.7 (78.3–119.6)

Socioeconomic status

I=58 (23.7)

I=47 (21.1)

I=3 (8.3)

 

II=90 (36.7)

II=94 (42.2)

II=7 (19.4)

 

IIIN=57 (23.3)

IIIN=34 (15.2)

IIIN=15 (41.7)

 

IIIM=35 (14.3)

IIIM=38 (17.0)

IIIM=11 (30.6)

 

IV=6 (1.6)

IV=9 (4.0)

IV=0 (0)

 

V=1 (0.4)

V=1 (0.4)

V=0 (0)

Cardiovascular disease

No=195 (79.6)

No=149 (66.8)

No=29 (80.6)

Historya

Yes=50 (20.4)

Yes=74 (33.2)

Yes=7 (19.4)

Cerebrovascular

No=203 (82.9)

No=189 (84.8)

No=26 (72.2)

Accident history

Yes=42 (17.1)

Yes=34 (15.2)

Yes=10 (27.8)

Mean systolic blood pressure (mm Hg)

148.9±19.0 (98.3–217.0)

149.8±17.5 (98.3–198.7)

146.3±20.3 (82.3–188)

Mean diastolic blood pressure (mm Hg)

78.6±9.3 (56.3–103.0)

77.2±9.3 (50.7–104.7)

77.6±11.1 (50.7–103.7)

Total cholesterol (mmol l−1)

5.3±1.1 (2.5–9.2)

5.1±1.5 (2.8–10.1)

5.4±1.2 (3.0–7.6)

LDL (mmol l−1)

3.1±1.0 (0.8–5.9)

2.9±1.1 (0.6–7.5)

3.1±1.3 (0.5–5.5)

HDL (mmol l−1)

1.5±0.4 (0.7–2.9)

1.4±0.4 (0.7–2.8)

1.6±0.5 (0.9–3.5)

Cholesterol/HDL ratio

3.7±1.1 (1.7–7.7)

3.7±1.1 (1.4–7.4)

3.8±1.3 (1.3–6.1)

Triglycerides (mmol l−1)

1.5±0.8 (0.4–4.5)

1.7±0.8 (0.4–4.3)

1.7±0.7 (0.6–3.1)

Diabetes history

No=224 (91.4)

No=193 (86.5)

No=34 (94.4)

 

Yes=21 (8.6)

Yes=30 (13.5)

Yes=2 (5.6)

HbA1c (%)

5.7±0.6 (4.4–8.6)

5.8±0.7 (4.8–9.1)

5.7±0.5 (4.6–7.2)

Forced expiratory volume (l)b

2.4±0.7 (0.4–4.2)

2.3±0.6 (0.8–3.9)

1.9±0.7 (0.8–3.25)

Hospital anxiety and depression scale score

2.3±2.0 (0–11)

2.7±2.2 (0–12)

2.9±2.2 (0–9)

Alcohol units per weekc

8.1±11.8 (0–84)

11.9±13.5 (0–63)

12.4±23.6 (0–120)

  1. Abbrevations: ANOVA, analysis of variance; HDL, high-density lipoproyein; LDL, low-density lipoprotein; MRI, magnetic resonance imaging.
  2. Results for continuous variables are reported as mean±s.d. (range).
  3. Results for categorical variables are reported as n (percentage).
  4. There are no statistically significant differences between groups, except for the three following variables:
  5. aCardiovascular disease history: χ2(2)=10.77, P=0.005; only contrast between subject that never smoked and ex-smoker is significant with Fisher’s exact test (P=0.002).
  6. bForced expiratory volume in 1 s: one-way ANOVA F (2501)=7.53, P=0.001; never versus current and ex versus current smoker contrasts significant with post-hoc Tukey’s test.
  7. cAlcohol units per week: one-way ANOVA F (2501)=5.11, P=0.006; only never versus ex-smoker contrast significant with post-hoc Tukey’s test.
Back to article page